In 1958, powder metallurgy was defined by the American Society for Testing and Materials as "the arts of producing metal powders and the utilization of metal powders for the production of massive materials and shaped objects." As a result of the demands imposed upon materials to be used to support high-technology components, powder metallurgy today has become more than just an art and the enhanced properties required of metal components to be utilized by modern technology has advanced its development into a science. The first consideration of powder metallurgy is, of course, the formulation of the powder itself. The characteristics of the final components are determined by the composition of the powder, together with the preparation of the ultimate alloy from elemental powders. Although considerable research has been conducted to develop metal powder compositions exhibiting a wide variety of properties for use in various applications, the specific metal powder composition described herein yields an alloy particularly suitable for the fabrication of components such as cylinder wall inserts for internal combustion engines or bearing surfaces where rigid dimensional tolerances, wear resistance, and elevated surface hardness are required.
It is an object of this invention to formulate a metallic powder which may be processed to provide an alloy exhibiting superior mechanical and physical properties and which provides increased wear resistance.
This and other objects of the invention will become apparent from the description which follows.
As used herein all percents and ratios are by weight unless otherwise indicated.